The ancestors of corals were found in the Ediacarian – 635ma (Fossils found in the
Flinders Ranges, Sth Australia)End of snowball Earth 2 Rise of Oxygen using Life Bloblike Animals in the sea, nothing on land. Australia Nth of Equator, Antarctica on the Equator & Amazonia at the South Pole supercontinent Rodinia collided with another continent forming the new supercontinent, Pannotia (all the continents, South Pole). Pan Africa – mountain building
In one of the Ancient Reefs like the enormous reefs over Wisconsin the corals (that had Nautiloids & Trilobites swimming about them) diverged into two groups.
One of these groups had sets of six tentacles
These became the Hexacorals
the Hexacorals split again to become the Hard Corals
soft coral jellyfish and anemones honeycomb and mushroom coral Bushy hard corals button coral